Dubowitz syndrome is a rare inherited disorder. Patients with the syndrome are clinically characterized by having eczema, recurrent infections, poor growth characteristics, and a unique facial appearance. The pattern of inheritance appears to be that of an autosomal recessive trait (i.e., the parents appear totally normal, but are carriers of the disease gene. The patients inherit one disease-causing gene from each parent, and thus have two disease genes and no normal ones). About ten percent of patients with Dubowitz syndrome develop profound blood disorders, including aplastic anemia, severe deficiencies of white blood cells, and lymphomas. Many patients have identifiable specific defects in immunity, particularly abnormalities of gamma globulin antibodies. The investigator proposes to characterize the spectrum of immunologic defects in the Dubowitz syndrome.